Dental appliance



May 28, 1946.

v. E. BRITT Eil-AAL DENTAL APPLIANCE Filed Dec. 29, 1944 2 Sheets-Sheet1 INVENTORS VERNON EARL 8,@/7'714/1/0` .man

May 2s, 1946. v; i; Bmw ET AL DENTAL APPLIANCE 2 Sheets-Sheet 2 FiledDec. 29, 1944 INVNToRs- VERNON EARL BQ/T'A/v Een/5T Ausf/5r 605725 vo. n

Patented May 28, 1946 UNITED STATES PATENT OFFICE DENTAL APPLIANCEVernon E. Britt and Ernest A. Goetze, Merced, Calif.

- Application December 29, 1944, serial No. 570,231

(ci. ca -26) 14 Claims.

Another object of the invention is to providean appliance of thecharacter described which can be incorporated with the dental handpiecewithout materially increasing the size or weight of the unit orinterfering with the normal use of the handpiece.

A further object of the invention is to provide an appliance of thecharacter described in which the supply of the` material to the toolwill be effected by operation of the handpiece and will at all times beunder the control of the operator.

A still further object of the invention is to provide an appliance ofthe character described` sectional view of the attachment shown inFigure 1.

` Figures 3 and 4 are transverse sectional views taken on the lines 3,-3and 4-4 of Figure 2.

Figure 5 is a side elevation of the'means of our invention embodied in aform different from that shown in Figures 1 and 2.

Figures 6 and 7 are enlarged fragmentary longitudinal sectional views ofthe forward and rear portions of the appliance as shown in Figure 5.

Figures 8 and 9 are transverse sectional 'views y of the appliance takenon the lines 8-8 and 9-9 of Figure 5. i Figure l0 is a transversesectional View of the appliance taken on the line I ll-I IJ of Figure;

in which the material to be delivered by the ap-` pliance can becontained in a magazine attached directly to or contained within thesupporting body of the handpiece and furthermore it is` an object topermit. replenishment of the supply of material in the appliance in avery easy and quick manner.

And additional object of the invention is to so design the appliancethat while the material is caused to pass through certain of therotating parts such as the tool supporting mandrel of the handpiecethere'will be no danger of any portion of the material escaping into thebearings or between any other of the surfaces of relatively moving partswithin the handpiece.

The invention Apossesses other objects and features of advantage, someof which, with the foregoing, will be set forth vin the followingdescription of the preferred form of the invention which is illustratedin the drawings accompanying 'and forming part or the specification.understood, however, that variations in the showing made by the 'saiddrawings and description may be adopted within the scope of theinvention as set forth in the claims.

` Referring to said drawings:

Figure 1 is a side elevation of the means of our invention as applied toa conventional dental handpiece, parts being broken away and shown insection` Figure 2 is an enlarged longitudinal vertical It is to beFigure 11 is a longitudinal sectional viewof av handpiece attachmentshowing a still further modified Vform of the invention.

As aboveset forth, the means of our invention is arranged to be appliedto a .dental handpiece and may be incorporated as a built in partthereof or combined therewitlrasanattachment. In the embodimentillustrated in FiguresV 1 and 2, the means is incorporated in anattachment or extension 4I2 designed to be affixed to an end VI5of ayconventional handpiece I3 to provide a contraangle head for holding thevarious dental tools, such as drill bits, grinding points `and the like.

In the design of dental handpiece illustrated, vthe handpiece includes ahollow supporting body I6 in which is mounted for rotation a tubularspindle I1 arranged to be driven by a pulley I8, the body being borne bya bracket I9 extending Y Vfrom an articulated frame 2|, on which iscarried driving parts for rotating the pulley in the well `known manner.In this type of handpiece, a chuck 22 is located Within the end portionI5 of the body I6 forreceiving and holding; the stem or mandrel of atool or the shaft of an extension member, such as a contra-angleattachment.

` `As here shown, the attachment I2 comprises a tubular body or housingformed of two `main sections 23 and 24, the section 23 being designed atoneend for attachment to the end I5 of the handpiece, while the section24 is secured to the other end 6 of the section 23 and -forms the heador tool bearing portion of the attachment. Attachment of section 23 tothe body I6 of the handpiece is preferably eiected by inserting the toengage the body I6, is in the form of a coupling 21 firmly secured tothe section and having an adapter portion 28 arranged to t over theportion |5.

Within the outer end portion 29 of the head section 2li is a mandrel 3|which is mounted for rotation in angular relation to the longitudinalaxis of the main body of the attachment in bearings 32 and 33 atopposite sides of the end portion 29. A driving connection for themandrel is afforded by means of a shaft 34 mounted in a bearing 36 inthe head section and having aflixed thereto a bevel gear 31 meshing witha bevel gear 58 aixed to the mandrel. Shaft 34 which is also angularlydisposed with respect to the axis of section 23 is connected by means ofauniversal joint 39 to a shaft 4| for detachable connection adjacent theend portion I with the spindle I1 of the handpiece |3. As will beunderstood, the outer end of shaft 4| is arranged to engage in the chuck22 when the end I5 of the handpiece is inserted'in the bore 26, and inthis manner when the attachment is operatively connected to thehandpiece, shaft 4| will be rotated by the spindle |1 in the same manneras a tool stem or mandrel inserted in the chuck.

As is well known, it is customary for dentists, particularly whengrinding or polishing a patients teeth, to apply to the teeth or thegrinding or polishing tool, a quantity of an abrasive or polishingsubstance usually in the form of a paste. This operation as heretoforeconducted involves frequent interruption of the grinding or polishingoperation, entails conduction of the operation with varying amounts ofthe paste, and

the application of the paste in an uncertain and relatively inefficientmanner. kIn View of the foregoing, our appliance is designed to provide,under control of the operator, a continuous and steady supply of anappropriate amount of the paste tothe tip'of the tool while the latteris being rotatedA andapplied to the teeth, the paste being withdrawnfrom an ample supply stored in a magazine or reservoir carried by theappliance. As will be clear from Figure 2, the mandrel 3| is positionedin the head portion 29 with one endfiZ protruding outwardly therefromand formed to receive and support thereat for rotation with the mandrela tool or tip such as the polishing cup 43. The mandrel, it will benoted, is formed with a longitudinal passage 44 which as here shownextends completely through the mandrel and is arranged to register withan Yopening or passage 46 provided in the tool 43 and leading totheexposed recess 41 therein. Means is provided for feeding to the .passagein the mandrel and into the opening 46, a continuous supply of thesubstance which is desired to be used in the operation such as theabrasive or polishing paste above referred to. Arranged as shown inFigure 2. within the body'section 23 of the attachment is a container ormagazine 48 having an outer shell 49 which is preferably 'formedseparate of and its the wall of the section and an inner shell 50 whichis disposed about Vthe shaft 5| and forms in part with the shell 59 astorage or supply chamber 5| for the'paste 52. One end of the containeri8 is closed by a, wall 53 vand has provided therein an outlet nipple 55which is connected as here shown by preferably fitted loosely againstthe passage walls and in order to provide against leakage or escape ofthe paste through the end 58, a stuffing box 59 is provided on theadjacent portion of the section 24 and formed to enclose the end 53 andthe connection 51. Desirably the walls of passage i4 are formed todiverge from the inlet to the delivering end as a means of facilitatingthe flow of the paste through the passage.

Asa means of forcing the paste from the chamber 5| into the variouspassages to the recess 41 in the tool, there is mounted forreciprocation in the chamber a. plunger 6| which engages the shell 59and has formed therein a central opening to accommodate the shaft 4| andthe shell 55 therearound. At the inner side of the plunger is prefferably provided a exible packing disc 52 formed means of a flexible tube55 to an elbow 51 leadingV directly into the mandrel passage Mat the end58 opposite the cup 53. Since the mandrel is designed to rotate, the`portion of the elbow or connection 51 disposed within the passage is toengage both shells, and. thus provide a sealed Vjoint thereat. As willbe clear, when the chamber 5l is filled with paste and the plunger is inthe retracted position shown in the drawings, on appropriate forwardmovement of the plunger the paste will be forced out through the nipple54, and thence through the tube 5i; and passages 44 and 46.

Movement of the plunger to force the material from the chamber 5! isarranged to be effected by power applied from the spindle l1. Forccnverting the rotative powerof the shaft to effect rectilinear movementof the plunger there is provided a screw 634 adapted to be rotated bythe shaft and having engaged therewith by means of a, correspondinglythreaded clutch 55, a stem 65 arranged to engage the plunger exteriorlyof the chamber. The screw is here shown in the form of an exteriorlythreaded sleeve surrounding the shaft and loosely fitted within the stemSS which is also preferably of tubular construction. Clutch Brtcomprisesa set of jaws 51 supported in a ring 68 slidably fitted in they section23 and havin-g an arm 59 riding in a slot 1| in the section to keep thering and jaws from rotating. The jaws are normally held in a retractedposition out of engagement with the screw, but may be moved intoengagement by a contraction ring 12 affixed to the end of stem G5 andheld from .rotating by an arm 1|! in the slot 1|, the contraction beingeifected when both rings are moved into cooperative relationship asillustrated in Figure 2. The rings may be held in operative relationwith the jaws engaged with the screw by meansof ay catch 13, and it willthus be clear that with the jaws held in contracted position, theclutch, the stem, and the plunger will be moved longitudinally when thescrew is rotated. It is` important to note that with the plungeradvancing means designed as thus described, no portion thereof includingthe screw will come in contact with the paste in the chamber, andfurthermore since the screw is not required to extend through theplunger or other part of the` container 45, the difficulty ofmaintaining the chamber in a sealed condition will be avoided.

Since the speed of rotation of the spindle and shaft is normallyrequired to be relatively high, such as-about 1800 revolutions perminute, it becomes advisable with the appliance in the form shown, toprovide for a considerable reduction in speed in respect to the screw inorder that the paste will be delivered to the tool gradually and of adesired quantity to the tool for a period of operation amounting toapproximately ten minutes. Then with the screw provided with 30 threadsper inch, and with a stroke of the plunger of approximately two inches,to substantially evacuate the chamber, it will be advisable that a speedreducing mechanism be operatively inserted between the shaft 4| and thescrew which will reduce the speed of the screw to approximately 6revolutions per minute. In accordance with the above, there isinterposed between the shaft and screw a speed reducing unit 14, or adesign which will provide for a maximum reduction in the speed withinminimum space, and as here shown the unit 'M is in the form of a chainof gears 15 to 80 inclusive, arranged in a planetary relationship in awell known manner; the gears l and 80 being secured to the shaft andscrew respectively. The unit 14 is positioned directly within a portionS2 of section 23 of the appliance preferably adjacent the end 28 andsuch portion can be readily enlarged as in the embodiment illustrated inFigures 5 and 6, to accommodate a larger size of said unit. Desirablythe unit is enclosed within a housing 83 which is fitted within theportion 82 and is secured against rotation relative thereto. A snap ring84 engaging the outer end of the casing and a groove in the portion 02is provided in order to hold the unit against longitudinal displacement.

Since the arm l0 projects from the slot such arm provides an indicatorfor apprisingthe operator of the progress of the plunger within thecontainer, and then he may readily guage the amount of paste remainingin the container, and as a positive as well as automatic means forpreventing the plunger from striking the end wall 53 of the container,the screw is foreshortened sufliciently so that before the plunger mayreach the wall, the jaws will become disengaged from the screw andthereby prevent further advance of the plunger by the screw.

As an important feature of the appliance, the container 48 is preferablymade in the form of a removable cartridge or capsule, so thatreplenishment of the paste in the appliance may be effected by simplyreplacing the empty container with a charged rell cartridge. Desirablythe plunger, and preferably the tube 56 are included as pre-assembledparts of the relled cartridge, and in this manner the contents thereofwill be kept in a clean and sanitary condition before, as well as after,the cartridge is inserted in the appliance, and. at the saine time therewill be no necessity for cleaning out any ofthe `passages leading fromthe cartridge to the mandrel. In order to facilitate ready removal ofexhausted cartridges and re-insertion of charged, the sections 23 and 2dare demountably connected at a point adjacent the end 53 of thecartridge, and are provided thereat with telescopic portions 86 and 87.which are frictionally held together, the portions being suitablyrecessed to accommodate the nipple 54, which extends from the containerand serves to maintain the sections in alignment and against rotationaldisplacement. In order to retract the stem in connection with therefilling operation, it is merely necessary to release the catch 13 andoperate the appliance with the shaft rotated in a reverse directionuntil the jaws are retracted sufficient to release them from engagementwith the screw threads, the clutch and stem members may then be freelyretracted manually to starting position and reengaged for the advancingoperation. i Y

In the embodiment Where the means of :our invention is incorporateddirectly as a part ofthe dental handpiece, delivery of the paste to themandrel will be arranged for irrespective of whether the mandrel issupported directly by the handpiece or is carried by an attachment 88applied tothe handpiece as an accessory thereto, as illustrated inFigures 5, 6, and 7. In this embodiment as illustrated, the handpiece 89has included therein the speed reduction means 9| which is here shown ofthe same design and construction as the unit 14 and is secured directlyto the spindle 92, the screw 93, and the clutch 94. Preferably the pastecontainer 9B is arranged to be removably carried on the exterior of thehandpiece housing 91 and affixed thereto by means of a spring clip 98,and the member 99 of the clutch is extended outwardly of the housing 91to engage the stem |0| which is arranged to bear against the plunger |02of the container 0. It will thus be clear that the functioning f thepaste expelling mechanism is similar in operation to the arrangementillustrated in connection with the first mentioned embodiment. Deliveryof the paste from the container to the man: drel is afforded by means ofa tube |03 which is attached at one end tothe outlet nipple |04 of thecontainer and at the other end to the mandre connection |06. i

It will be noted that since the paste container is associated with vthehandpiece not only can the attachment be of relatively short length butthe exterior thereof,as in the previous embodiment, is devoid of anyobstructive protuberances, and therefore the appliance may be insertedwithin the oral cavity and otherwise operated with the same facility asappliances which lack the advantages of the present invention.

In Figure 1l `we have shown an additional form of the invention of thetype in which the paste supply means is incorporated with the attachmentrather than to the hand piece. i The structure in this embodiment is ofa more simpliiiednature than as shown in Figure 1. The plunger -SI' ofthe paste container 48' is simply threaded for engagement with the screw63 which is rotatably supported in a bearing portion in the end wall 53of the container so that upon rotation of the screw theA plunger will beadvanced to expel the paste.

We claim:` l l. In a dental appliance, the combination with a dentalhandpiece having a tubular body member and a rotatable spindle mountedtherein and operatively associated with a chuck adjacent one end of saidmember` of a'tubular extension member detachably secured to said bodymember at said end thereof, a shaft mounted for rotation in saidextension member and detachably engaged at one end with said chuck, atool mandrel carried by said extension member and operatively connectedto the other end of said shaft and having a passage extendinglongitudinally therethrough, a polishing tool carried at one end of saidmandrel having an opening exposed thereon and communicating with saidpassage, a maga-` zine containing an abrasive `or the like carried byone of said members and with the interior in communication with saidmandrel passage, an ejector mounted for movement in said magazine forexpelling said abrasive therefrom intosaid passage, and a drivingconnection between said shaft and ejector.

2. A dental appliance in accordance with claim 1, in which said magazineis positioned within said extension member.

-of said body having a driving connection with said unit and providedwith a passage therethrough, an abrading tool carried by said mandrelexteriorly of the body and having an opening communicating with saidpassage and leading to the exterior of the tool, a reservoir forabrasive material carried by said body member and having the interiorthereof in communication with Vsaid passage, and means operative by saidrotatable unit to discharge the material from said reservoir into saidpassage on rotation of the unit.

5. In a dental appliance of the character described, a tubularbody'member, a driving unit extending longitudinally through saidmember, a rotatable mandrel supported in said member in angular relationto said unit and having a passage therethrough, a tool carried by saidmandrel at one end thereof and outwardly of the body and having anopening in communication with said passage, a reservoir for paste or thelike carried by said member, a conduit from said reservoir extendinginto said passage, and power operated means operating independently ofsaid tool for expelling the material from the reservoir through saidconduit.

6. In a dental appliance of the character described, a tubular bodymember, a driving unit extending longitudinally through said member, arotatable mandrel supported in said member in angular relation to saidunit and having a passage therethrough, a tool carried by said mandrelat one end thereof and outwardly of the body and having an opening incommunicationwith said passage, a reservoir for paste or the likecarried by said member, a conduit from said reservoir extending intosaid passage, means for expelling the material from the reservoirthrough said conduit and a speedA reduction means operativelyconnectedto said unit and with said ejector means.

7. In a dental appliance of the character described, a tubular bodymember, a driving unit extending longitudinally through said member, arotatable mandrel supported in said member in angular relation to saidunit and having a passage therethrough, a tool carried by said mandrelatone end thereof and outwardly of the body and having an opening incommunication with said passage, a reservoir for paste or the likecarried by said member, a conduit from said reservoir extending intosaid passage, means for expelling the material from the reservoirthrough said conduit, a speed reduction means connected to said unit,and means releasably connecting Said reduction meansrto said ejector toadvance the ejector upon rotation of said unit.

8. In a dental appliance, a tubular body member having a hollow headsection and a hollow body section providing a handle for themember, ashaft mounted for rotation in said body handle section and having anextension positioned within said head, a rotatable mandrel mounted insaid head in angular relation to said shaft and having a drivingconnection therewith, said mandrei having a longitudinal passageextending therethrough, a tool arranged for mounting on said mandrel toproject outwardly of said head, a

fixed conduit extending through said head and into Yengagement with saidmandrel in communication with said passage, a stuffing box about saidconduit and the portion of the mandrel with which it is engaged, and areservoir for paste carried by the handle section of said member havingthe interior thereof in operative communication with said conduit. V

9. In a dental handpiece, a tubular body member providing a handleportion, a unit mounted for rotation therein, a speed reduction meansfor said unit adjacent one end of said body, a rotatable mandrel at theother end of said body having a driving connection with said unit andprovided with a passage therethrough, an abrading tool carried by saidmandrel exteriorly of the body and having an opening communicating withsaid passage and leading to the exterior of the tool, a reservoir forabrasive material carried by said body member along said handle portionand having the interior thereof in communication with said passage, andmeans operatively connccted with the speed reduction means for forcingthe material from the reservoir for supply to said tool.

10. In a dental appliance for supporting a rotatable tool carryingmandrel, a tubular body member providing a handle portion, a rotatableunit mounted therein and having a connection with said mandrel forrotating same, a cartridge removably fitted Within the handle portion ofsaid body andv arranged to contain a charge of material of paste-likeconsistency and having a discharge opening therein, a plunger in saidcontainer mounted to expel the material upon advance therein, meansextending through said handle portion for advancing said plunger, andmeans providing a passage from said discharge opening to said mandrel.

11. A dental appliance in accordance with claim l0, characterized by atube extending through said cartridge and said plunger and surroundingsaid unit and combining with the cartridge walls to seal the contentsthereof from the exterior of the cartridge.

12. In a dental appliance, the combination with a dental handpiecehaving a tubular body and a rotatable unit mounted therein and arrangedto have a tool mandrel carried by the unit, a cartridge removably fittedwith'in said body and arranged to contain a charge of material ofpastelike consistency and having an outlet therefrom, a connection fordelivering material from said outlet to said mandrel, said cartridgehaving affixed thereto a tubular portion itting around said unit andsealing the material therefrom, a plunger mounted in said cartridgemovable therethrough to expel the material through said outlet, a sternengaging said plunger outwardly of said cartridge, a rotatable threadedsleeve surrounding said unit and arranged for operative connection withsaid stem to move the stern longitudinally of said body and advance saidplunger on rotation of said unit, and means interconnecting said unitand sleeve to reduce the relative speed of rotation of said sleeve withrespect to said unit.

13. In a dental appliance, the combination with a dental handpiecehaving a tubular body and a rotatable unit mounted therein and arrangedto have a tool mandrel carried by the unit, a cartridge removably fittedwithin said body and arranged to contain a charge of material ofpastelike consistency and having an outlet therefrom, a, connection fordeliveringmaterial from said outlet to said mandrel, said cartridgehaving affixed th'ereto a tubular portion fitting around said unit andsealing the material therefrom, a plunger mounted in said cartridgemovable therethrough to expel the material vthrough said outlet, ahollow stem operativelylengagin'g the said plunger outwardly of saidcartridge and disposed about said unit, a rotatablescrew threaded sleevepositioned within said stem and surrounding said unit and part of thetubular portion of the cartridge, a speed reduction meansinterconnecting said unit and sleeve to rotate th'e sleeve at a lesserspeed than the unit, and a clutch member releasably and operativelylconnecting said sleeve and stem for relative longitudinal displacementupon rotation of the sleeve.

14. A dental appliance adapted for attachment to a dental handpiecehaving a rotatable tool chuck, comprising a tubular body, a pastecontainer removably tted within said body, a shaft extending throughsaid cotnainer and arranged for operative connection with Vsaid chuck, arotatable mandrel carried by said body operatively l connected forrotation with' said shaft, means to convey the paste from the containerto the mandrel, a screw surrounding said shaft and extendl0 ing throughsaid container, a plunger fitting in saidA container and supported.therein for longi-V,

15 between said screw and shaft.

,VERNON E. BRITT.

ERNEST A. GoETzE.

